 
 (defn noise-to-tiles
   [x y noise]
-  (tile
+  (mk-tile
     (cond
       (< noise 0) :air
       (< noise 0.15) :dirt
       :else :stone)))
 
 (defn grow-grass
-  [tiles x y t]
+  [tiles x y tile]
   (if (and
-        (= (:kind t) :dirt)
+        (= (:kind tile) :dirt)
         (= (:kind (tile-at tiles x (dec y))) :air))
-    (tile :grass)
-    t))
+    (mk-tile :grass)
+    tile))
 
 (defn new-chunk
   [width height]

    (letfn [(new-column [bound]
              (let [dirt (rand-in-range 1 4)]
                (vec (concat (repeat (- height bound)
                                     (tile :air))
                             (repeat dirt  (tile :dirt))
                             (repeat (- bound dirt)
                                     (tile :stone))))))]
      (vec (map new-column mrange)))))

(defn new-coord-map

                  :air true
                  :ore false})

(defn mk-tile
  [kind]
  {:kind kind
   :passable (passability kind)})

